Method of cutting leaders, gears, or racks



M. E. FERNALD METHOD OF CUTTING LEADERS, GEARS, OR RACKS June 14, 1927.

Filed Jan. 3. 1923 4 Sheets-Sheet l June 14 1927. 1,632,396

, M. E. FERNALD METHOD OF CUTTING LEADERS, GEARS, 0R RACKS Filed Jan 5. 1925 4 Sheets-Sheet 2 //v vE/v TUE 1,632,396 June "M. E. FERNALD METHOD OF CUTTING LEADERS, GEARS, OR RACKS Fild Jan. s, 1923 4 SheetS -Sheet 5 //v VEN 727R June 14, 1927. E. FERNALD 1,632,396

METHOD OF CUTTING LEADERS, GEARS, 0R RACKS Filed Jan 5, 1923 4 sheets sheet TI/AFI VIIIIIIIIIIII4 Patented June 14, 1937;

tenses stares PATENT rric.

MARK n. FERNALID, or SOUTHBOR-O, MASSACHUSETTS, aseronoa ro o. c. BLAKE, m oozreonarnn, or Bos'rou, MASSACHUSETTS, A ceases-Arron onivnw YGRK.

METHOD or CUTTING LnAnnas, Guess, on aeoirsf' Application filed January 3, 1823. Serial No. 610,442.

g 'i' re present invention relates to the art of cutting tooth on leaders, gears, racks, and similar machine elements which are provided with teeth or some equivalent members by which they are fed or by which they feed some other member. Specifically, the invention relates to the art of cutting teeth on sole-shaped leaders which are used in the manufacture of Blake welt shoes to guide the work through an automatic shoe machine during its operationupon the shoe or a step product thereof. These sole shaped leaders vary in size and style with the various sizes and styles or the insoles of the shoes to be operated upon and consequently the peripheries of the leaders vary in length.

l leretoi'ore, in plotting the teeth on the leader, the length of its periphery would first be determined and then this dimension would be divided by the number of desired teeth to determine the circular pitch or distance between tooth centers necessary to evenly space the desired number of teeth around the periphery of the leader. As these peripheries vary inlength, it is apparent that a circular pitch which would evenly space the teeth around one leader would cause an errorin the spacing of the teeth on another leader designed for a different size or style of shoe.

The object of the present invention is; to devise a method oi cutting teeth on leaders, gears and racks in which a standard circular pitch may be employed for all the varying sizes of the machine elements of this general class, while permitting substantially an even spacing of the teeth around the var ying peripheries. i

To the accomplishment of this object and such others as may hereafter appear, a tea are of the present. invention consists in a nethod of making leaders, gears and racks hich consists in providing a suitable blank for a leader, gear or rack; cutting teeth having a predetermined circular pitch along said blank: stopping the cutting of said teeth with the blank short a predetermined num-- ber of teeth: determining the amount of the er pitch necessary to evenly space the ting uncut portion of the blank, and

then cutting the said predetermined num-" redetermined number of teeth in the her 0t teeth having the determined circular pitch to finish the blank. With this method, the error, any, is found and divided up among all the predetermined number of teeth. In some cases, the new circular pitch will be slightly more than the predetermined circular pitch and in some cases, the new circular pitch willbe less. In every case, however, the new circular pitch will vary but slightly tromthe predeterminedcircular pitch so no difficulty will be experienced in driving the finished leaders in the automatic shoe machines. i V

- I propose to practice the improved method of making leaders, gears and racks in connection with v the machine disclosed' in my Patent No. 1,284,882, patented November 12,

1918. i I" propose to insert a suitable blank for tl'ie'leader, gear or rack into thismachine and to adjust the feed thereof in accordance with a predetermined circular pitch for the teeth and then stop the cutting operation'of this machine withthe'blanlrshort a predeterminedni'nnber of teeth. I then propose to'measure the space between the first and last cuts and then determine from this measurem'entjwhat circularpitch is required to evenly space the predetermined number of teeth in the uncutportionot-theblanlr, and then to readjust the feed of the machine to impart the new determined circular pitchto the teeth in theuncut portionnojf the blank when the cutting operation of themachine is resumed. I i

"The various features ofthe'present invenisa detail in plan ofthe feeding Figure 5 is view similar to Figure 4' showing the connectionsbet-ween the clutch actuator and trip and the automaticstop; a Figure 61s a plan of a "solexshaped leader blank having the teeth formed on the periphery thereof, but leaving the blank short a predetermined number of teeth;

Figure is a detail of one of the leader cams or trips; i

Figure 8 is a sectional elevation showing I the cam or trip in place on the leader;

Figure 9 is a plan of a Vernier used in determining the circular pitch in the remaining uncut portion of the blank;

Figure 10 is a side elevation of the vernier and Figure 11 is a sectional elevation on the line 11-11, Fig. 10.

Briefly described, the machine shown comprises a work supporting table 12 (Fig. 1) on the surface of which the leader blank 13 is freely movable; a cutter 14L arranged to 'move up and down past said table and operative to make tooth-cuts in the peripheral edge of the blank; a work feeding finger 15 2) which operates on each toothcut immediately after it is formed. to feed the blank past the cutter into-position for the next cut; additionalmechanism 16 and 17 (Figs. 1 and 2) that acts on the blank to position it in the proper'angular relationship to the'cutter for the next cut; and a clamp 18 which holds the work in the new position to which it is adjusted by these mechanisms while the cutter makesa tooth-cut and then releases the work again for the next feeding and positioning movements.

The inside stud 17 is mounted on a bell crank lever 19 (Figs. 1 and '5) which is fulcrumed on a pin 20zsupported by a part of the table 12. .A link 21 and a bell crank lever 22, one armof which forms a handle and the otherarm of which is'pivotedto the link 21, constitute atoggle mechanism designecl'to hold the stud 17 in a fixed position against the inside, face of the flange on the leader 13.

In the 1machineillustrated in the drawings, the extent'of the feeding movement; of

- the finger 15 (Fig.2) is controlled by a stop 23 formed on one end of a rod 2 1 which extends through the sides of the table 12.

' Near one end, the rod 24 is threaded to ro- '29 having" a scale 30 thereon.

the scale. The tooth 31 by engagei'nent with one of the slots32' locksthe arm in any position of adjustment. The construction and arrangement of the connections between'the arm 28 and'the stop 23 provides a very fine adjustment of the extent of the feeding movement of 'the. leader blankQ Consequently, the stop 23 should be set in accordance with the circular pitch of the teeth to be cut in the leader.

In preparing the leader blanks for operation by themachine of the drawings the leader blanks are provided with a pair of holes 33 and 34 (Fig. 6). These holes are drilled in the leader blanks with the aid of a jig (not shown) which is constructed to space the holes a distance equal to a predetermined number of teeth, for instance, twenty, having a predetermined circular pitch.

After the, holes 33 and 3 1 are formed, a pair oftrips or cams 35 and 36 are inserted therein. Each of the trips comprises an expansible body portion 37 (Fig. 7 and an oflset portion 38 arranged to engage the bottom faceiof the leader blank. When the trips are first inserted into the holes the offset portions 38 are oppositely disposed relatively. That is, the offset portion 38 on the trip 35 is arranged on the right of the center of the body portion 37, while the offset portion 38 on the trip 36 is arranged on the left of the center of the body portion.

The leader blank, with the trips in place thereon, is now inserted into the machine with the stop 23 adjusted to permit the feed to impart a predetermined circular pitch to the teeth. The leader blank is so positioned in the machine that the first tooth cut will be the one marked 39 (Fig. 6) and the direction of feed is such that the cutting of the teeth will proceed in the direction of the arrow.

In order to automatically stop the machine with the blank short the twenty teeth; the machine is provided with an automatic stop which operatesupon engagement with the trip 35 to throw the driving mechanism out of action. 7 v

The machine may be driven in any con- Veni-ent manner. In the arrangement shown an electric motor 10 is supported on a suit able bracket 11 mounted on the machine mounted'on' the main shaft 13f This pulley is designed to be operatively connected to the main shaft 43 by a clutch 14 splined on the shaft. The hub of the clutch is provicled with a yoke and strap connection with "an arm 15 which is pivoted on a bracket 16 carried by the gear housing 1?. The upper'end of the arm 15 is pivoted to a rod48 which slides loosely through a boss 49 formed on the bracket 16. The rod 48 is pivoted to one end of a link 50 the other end 'of which-ispivoted to .the horizontal arm 51 of a bell crank lever handle 52'pivoted at .53 on the machine frame. 51 and link 50 constitute a toggle which when made throughmanipulation of, the handle 52, actuates the clutch a4. to throw the drivingmechanism into action. I'Vhen base and is belted to a pulley 12 loosely 7 The arm nut 74: secures the screw 73 the'clutch is actuated, a'spi'ing 54 connecting the bracket 4:6 and arm is tensioned'i In order to hold the toggle in its made position against the tension or the spring 54 a boss 55 on the link 50 is provided with a notch 56. The notch 56 is engaged by a hook 57 pivoted on themachine frame. The hook 57 is actuated in a direction to engage the notch 56 by a spring 58. The hook 57 maybe n'ianually tripped in order to restore the toggle to the influence of the spring 54; by a bell crank 59, pivotcd on the arm 51, and normally held separated from the handle 52 by a spring 'interp0sed between the bell cranks.- The lower end of the arm 59 is provided with a foot 61 whichywhen the toggle is made, rests. against a cam surface 62 torme'don the hook 57. With this construction, actuation of the bell crank 59 towards the handle 52 against the tension out the spring 60causes the foot 61 engaged with the cam surface (32 to turn thehook 57-011 its pivot out of engagement with the notch 56. The spring 54 thus is free to break-the toggle and withdraw the clutch a l from driving engagement with the driving mechanism. To limit the moven'ient oi the toggle when it is broken, the machine frame carries an adjusting screw 62 which limits the upward movement of the 51.

In order to automatically disengage the hook 57 from the notch 56 and thus automatically throw the driving mechanism out of action, a stop 63 (Fig. 2) is positioned to extend above the stud 1?. The stop 63 is pivoted at 64 (Fig. 2) on the bell crank 19 and is normally held against a pin 65 on the bell crank 19 bya spring pressed pin 66 working in a chamber 6'? formed in the bell crank 1.9. hen the stud 17 is in operative position, the pin 66 engages a rod 68 ,which slides through the table 12 below the surface thereof.

The rod 68 at the point where it extends outside the side of the table 12 engages one arm of a bell crank lever 69 pivoted on a bracket 70 carried by the side of the table 12. The other arm of the bell crank lever (39 engages one end of a rod 71 mounted to slide freely in brackets 72 carried by the side or the table 12 and machine frame re spectively (Fig. 1). The other end'ofthe rod 71 (Fig. 4) engages a screw 73 carried by the' lower end or the hook 57. A look position.

lVith the construction described, the machine automatically cutsteeth -around the periphery of the blank until the stop 63' in its adjusted toggle and throws the driving mechanism out of action. r

With the machine stopped, the "operative measures the distance on the blank between the first and last cuts in order to find the distance in which it is necessary to evenly space the remaining twenty teeth. The operative may i'ind upon. measuring the space referred to that no change in the circular pitch just used to cut the teeth is required, or hemay find that the space is too long or too short for the twenty teeth. It the space is too long, the excess space'is found and divided by twenty in. order to find the amount to be added to the circular pitch in order to evenly space the twenty teeth. Conversely, it the space istoo short for the twenty teeth, the amount whiclrthe space is short is divided by twenty to iind the 'ain-ounttobe subt "acted from the present circular pitch in order to evenly space the twenty teeth. In any case, whether the spaceis too long or too short, the error Whendivided up among twenty teeth is very small and consequently no substantial change is made in the circular pitch.

,To provide the operative with an. easy way to immediately determine the new circular pitch by inspection, the instrument shown in Figs. 9 and 10 isprovided. This instrument is provided with a true scale 7 5 and a vernier scale .76. The true scale 7 5 slides in ways 77 (Fig. 11) formed in the vernier scale 76. The true scale is held in any position of adjustment by a head 78 arranged to pass through the vernier scale 7 6 and wedge against the true scale 7 5. The head 7 8 is formed on a bolt 79 which passes loosely through an arm 80 one end or which engages the bottom of the vernier scale 76. The other end of the arm 80 is engaged by a spring 81, the construction being such as to wedge the head 78 against the true scale 75. To release the pressure on the true scale 75,

the

the operative merely presses the springpressed end of the arm '80 thus releasing the pressure and permitting the true scale? 5 to slide'freely in the'vernier scale. p

The vernier scale 76 is provided with a tooth 82 and thetrue scale 75 is provided with a tooth 83. The teeth 82 and 83 are arranged to engage the firstand last cuts respectively in the leader blank to measure the space. remaining uncut. The true and vernier scales are of equal length, although the true scale is provided withtwenty equal divisions, while the vernierscale is provided with twenty-one equal divisions. nier scale is also divided into a longside and The vera' shortside. WVith this instrument, two divisions on the true scale wlll always be 013-;

posite two divisions on the 'vernier'scale but if the tooth 82 is on the right of thezero mark 84 on thetrue scale, the operative takes the two divisions on the longside for the reading. Conversely, if the tooth 82 is on the left of the zero mark 84: on the true scale, then the operative takes the two divisions on the short side for the reading. This reading may beq5 short or 3 long, for instance. v If it is 5 short, the operative shifts the arm 28 (Fig. 3) to 5 on the short side of the scale 30. If it is 3 long, the operative shifts the arm 28 to 3 on the long side of the scale 30., In doing this, the operative adjusts the feed of the machine so that when the machine is restarted, it will cut teethevenly spaced in the now uncut portion of the blan Before restarting the machine, theoperatlve removes the trip 33 and shifts the trip 34 around so that the offset portion 38 thereon is positioned on the right of the center of the trip (Fig. 6). The machine will then automatically cut the'twenty teeth in the blank, whereupon the stop 63 will, upon engagement with the trip 36, automatically stop the machine through'the connection with the hook 57. The finished blank is then removed from themachine and the arm 28 [shifted back to the zero mark on the scale 29.

In the event thatthe machine has been takencdown for repairs and it is desirable to set the feed for a standard pitch preliminary to cutting teethon leader blanks, a. trial blank is inserted into the machine and twenty teeth cuttherein. These teeth are then measuredon the instrument shown in Figs.

' .9 and 10, the reading of which will indicate and brings the armJQSback to zero, thereafter tightening screwQG.

It 1s highly desirable in-machines of this general class in which the work isengagcd by aflplurality of operating instrumentalities to stop the machine in apredetermined position with the operating devices out of contact with the work and thus enable the operative to withdraw the work readily. To this end, the arm (-Fig. .1) carries a shoe SS which when the toggle is broken is engaged with a brake Set on the shaft 43.; As the automatic stop operates duringthe feed of the leader, at whic'hiime the cutter 14: and clamp 18 are'out of contact with the worlnthe brakejoperates to stop the machine at a time when the work is free to be withdrawn from the table 12.

Vhile thenumber of teeth left uncut in the blank at the time of the first automatic stopping of the I machine is described as twenty, it must be understood that this numher is arbitrary as the method of cutting leaders,gears or racks herein disclosed may be practised successfully by adopting any other number of teeth with the general limitation that the number of teeth selected be sufiicientto apportion the error so that for each tooth, the variation from the circular pitch be very small. I

blank; stopping the cutting of said teeth with the blank short a predetermined number of teeth; determining the amount of circular pitch necessary to evenly space the said predetermined number of teeth in the remaining uncut portion of the blank, and then cutting the said predetermined number of teeth having the determined circular" pitch-to finish the blank.

2. That improvement in the process of making leaders, gears and racks which consists in providing a suitable blank for a. leader, gear or rack; cutting teeth having a predetermined circular pitch along said blank; stopping the cutting of said teeth with the blank shorta predetermined number of teeth; measuring the uncut portion on the blank and dividing this length by the predetermined number of teeth to determine the amount of circular pitch necessary ;to evenly space the said predetermined number of teeth in the remaining uncut portion of the blank; andthen cutting the said predetermined number of teeth having the determined circular pitch to finish the blank.

3. That improvement in the process of making leaders, gears and racks which con sists in providing a suitable blank for a leader, gear or rack; inserting the blank nto a cutting machine having its feed ad justed to a predetermined circular pitch, op-

crating the machine to cut teeth having the predetermined circular pitch along said blank; automatically stopping the machine when the blank has been provided. with all but a predetermined number of teeth; measuring the distance remaining uncut on the blank to determine the amountof circular pitch necessary toevenly space the said predetermined number of teeth in the remaining uncut portion of the blank; changing the feed of the machine in accordance with the determined circular pitch; restarting the machine to cut the said predetermined number of teeth having the determined circular pitch, and automatically stopping the machine upon the completion of the cutting of said predetermined number of teeth.

4. That improvement in the process of making leaders gears'and racks which consists in providing a suitable blank fora leader, gear or rack; providing the blank with a pair of trips or cams spaced apart a distance equal to a predetermined number of teeth having a predetermined circular pitch; inserting the blank into a cutting machine having its feed adjusted to the predetermined circular pitch; operating the machine to out teeth having the predetermined pitch along said blank; stopping the machine upon engagement With one of the trips; measuring the distance remaining uncut on the blank to determine the amount of circular pitch necessar to evenl s )a-ce the said aredetermined number of teeth in the remaining uncut portion of the blank; changing the feed of the machine in accordance With the determined circular pitch; restarting the machine to cut the said predetermined number of teeth hav ing the determined circular pitch, and stopping the machine upon engagement with the second trip on the blank.

5. A machine for use in the manufacture of shoes, having, in combination, a leader, an operating tool, driving mechanism connected with one of said parts to cause the point of operation of the tool to be transferred around the leader, and means controlled by the leader for throwing the driving mechanism out of action.

6. A machine for use in the manufacture of shoes, having, in combination, a leader, a stopping device thereon, an operating tool, driving mechanism for moving the leader to transfer the point of operation of the tool around the leader, and means operated by the stopping device for throwing out the driving mechanism.

7. That improvement in the art of adjusting a machine for cutting leaders, gears, and racks Which consists in inserting a trial blank in the machine and cutting a prede termined number of teeth thereon, stopping the machine and determining the variations, if any, in the circular pitch in the teeth cut from a predetermined circular pitch, and

then adjusting the feed of the machine to,

compensate for the determined error.

8. A machine, for use in the manufacture of shoes, having, in combination, a leader, an operating tool, driving mechanism for moving the leader to transfer the point of operation of the tool around thevvork, devices operating during the movement of the leader for throwing the driving mechanism out of action, and means for bringing the machine to rest With the operating tool Withdrawn from the Work.

9. A achine for use in the manufacture of shoes, having, in combination, a leader, an operating tool, driving mechanism for moving the leader to transfer the point of operation of the tool around the Work, means controlled by the leader for throwing the dll'lV? ing mechanism out of action, and means for bringing the machine to rest With the operating tool Withdrawn from the Work.

10. A machine for use in the manufacture of shoes, having, in combination, a soleshapcd blank, an operating tool, driving mechanism for moving the blank to transfer the point of operation of the tool around the blank, and devices for throwing the driving mechanism out of action operating at any desired point along the periphery of the blank.

In testimony whereof I have signed my name to this specificatlon.

MARK E. FERNALD. 

